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Please use public-script-coord mail list for Web IDL

From: Arthur Barstow <art.barstow@nokia.com>
Date: Wed, 04 Aug 2010 18:05:05 -0400
Message-ID: <4C59E411.2040709@nokia.com>
To: Travis Leithead <travil@microsoft.com>, public-script-coord <public-script-coord@w3.org>, public-webapps <public-webapps@w3.org>
Hi All,

Please use public-script-coord for Web IDL.

-Thanks, AB

-------- Original Message --------
Subject: 	RE: [WebIDL] interface objects and properties too restrictive?
Date: 	Wed, 4 Aug 2010 20:36:00 +0200
From: 	ext Travis Leithead <travil@microsoft.com>
To: 	Jonas Sicking <jonas@sicking.cc>
CC: 	Cameron McCormack <cam@mcc.id.au>, "Sam Weinig (weinig@apple.com)" 
<weinig@apple.com>, "public-webapps@w3.org" <public-webapps@w3.org>



Sure.

Not only does ES5's configurable: false property prevent deletion, but it also prevents changing a property from a field to an accessor and vice-versa, as well as changing the getter/setters of the property.

So, the following wouldn't work if the "appendChild" property was configurable:false:

Object.defineProperty(Node.prototype,
                       "appendChild",
                       { get: function() { /* custom getter replacement */ },
                         set: function(x) { /* custom setter replacement */ }
                       });

... which is the ES5 way of doing:
Node.prototype.__defineGetter__("appendChild", function() { /* custom getter replacement */ });
Node.prototype.__defineSetter__("appendChild", function(x) { /* custom setter replacement */ });

So, configurable: false prevents users from replacing built-in properties with getter/setters. I think this is too restrictive, especially forward-looking considering how much the DOM is changing and evolving.

-----Original Message-----
From: Jonas Sicking [mailto:jonas@sicking.cc]
Sent: Tuesday, August 03, 2010 5:22 PM
To: Travis Leithead
Cc: Cameron McCormack; Sam Weinig (weinig@apple.com); public-webapps@w3.org
Subject: Re: [WebIDL] interface objects and properties too restrictive?

On Tue, Aug 3, 2010 at 4:57 PM, Travis Leithead<travil@microsoft.com>  wrote:
>  Hey folks, just wondering what the justification behind the current
>  {DontDelete} semantics are in WebIDL 4.4 [1] and 4.5 (second bullet)
>  [2]. When our IE9 binding ported this to ES5, it translated to
>  "configurable: false", which completely destroyed the ability to set
>  accessors on the interface objects as well as operations (and in our
>  case, DOM accessors). Because of this, we actually don't mark our
>  interface objects OR operations/attributes as configurable: false,
>  rather configurable: true.*
>
>  If this seems reasonable, I'd like to see the spec updated.

Sorry, I'm not very updated on the differences between the ES3 and ES5 worlds. Why does "configurable: false" destroyed the ability to set accessors? Can you give an example of a piece of script that doesn't work but which you'd like to work, and what you'd like it to do?

/ Jonas
Received on Wednesday, 4 August 2010 22:05:49 GMT

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